One of the more interesting behind-the-scenes additions in Android 5.1 is a new carrier provisioning API that provides functionality which likely benefits carriers and customers alike. Any time you join a carrier, you get services along with your account, whether it's Play Store billing, visual voicemail, premium subscription services billed to your account, or any number of other things. For as long as Android has existed, the methods used to provision these services on a customer's account have varied widely from carrier to carrier, and there was no standard way of doing it.

DirecTV's job used to be making sure that when you turn on your TV, there's something there to watch. Then these fancy mobile devices came around, and now the company is tasked with putting shows on those as well. Kids don't stare at big screens anymore, I'm told. Everything looks best crammed somewhere between 4.5 to 10.1 inches.

The latest version of the DirecTV Android apps offer up 15 new HBO and Cinemax channels, which you can stream live to your phone or tablet.

Android 5.1 made some major changes to the way recent apps are handled in Android. You can include Chrome tabs in the recent app list, and apps that are called up from another activity get their own card to keep things more consistent. However, Google also decided to never clear the list of recent app cards. It just goes on and on and on... it's kind of annoying. "Recently" from Chainfire fixes that, but you need root.

Google is progressively rolling out the full array of releases for Android 5.1, and the SDK is now joining the ranks. If developers open up the SDK Manager today, they will find a brand new software development kit for API 22. The SDK package is there, along with the typical documentation, samples, source code, and an assortment of system images for each of the major hardware architectures. All is ready to start updating apps to take advantage of everything Android 5.1 has to offer.

Moto Maker makes ordering a Moto X different from picking up any other smartphone. You get to customize the handset to suit your own peculiar tastes, even if that means picking an appalling color pattern and nonsensical engraving that all but guarantee you won't be able to sell the thing at any point in the future.

Android 5.1 seemed like a very minor update when it was announced, but there are actually a lot of cool little changes throughout the OS. For example, you can now (finally!) change the system volume while you have audio playing. Google added a new button to make this happen.

Back in October, we posted a quick look at some of Google's very early plans for multi-window functionality on Android Lollipop, a feature that had apparently been in the works since at least KitKat. The system, in a nut shell, would allow users to have two apps open at a time, scaling the apps to take up more or less space on the screen, and interact with the overview or Google Search, passing text or other data back and forth.